Material dispensing control system

ABSTRACT

An electronic system produces a train of electrical pulses or signals for controlling the dispensing of materials in different amounts or proportions, such as desired in the automatic batching of concrete. By control settings preset on a main electronic decimal counter, a prescribed number of pulses is delivered by the system to a mechanical analog device which in turn controls the material-dispensing mechanism. Additional presettable electronic counters are combined with the main decimal counter to achieve any number of batch formulations proportioned on the basis of arithmetic ratios established by the control settings selected on the counters.

United States Patent [72] Inventors John L. Hill;

Neil B. llowes, both of St. Paul, Minn. [2]] Appl. No. 769,822 [22]Filed Oct. 23,1968 [45] Patented Sept. 14, 1971 [73] Assignee RamseyEngineering Company St. Paul, Minn.

[54] MATERIAL DISPENSING CONTROL SYSTEM 14 Claims, 4 Drawing Figs.

52 11.5. CI 235/92 PE, 235/92 CC, 235/92 FL, 2351151.] [SI] Int. Cl11031: 21/36 [50] Field of Search 235/92, 151.1

[56] References Cited UNITED STATES PATENTS 3,229,077 1/1966 Gross235/15 1.34

I 2 BINARY COUNTER I NII'IAL STIMULUS POWER IN BINARY COUNTER 2,997,2348/1961 Hughes 3,163,747 12/1964 Veverka Primary Examiner-Maynard R.Wilbur Assistant Examiner-Robert F. Gnuse Attorney-Bugger, Peterson,Johnson and Westman ABSTRACT: An electronic system produces a train ofelectrical pulses or signals for controlling the dispensing of materialsin different amounts or proportions, such as desired in the automaticbatching of concrete. By control settings preset on a main electronicdecimal counter, a prescribed number of pulses is delivered by thesystem to a mechanical analog device which in turn controls thematerial-dispensing mechanism. Additional presettable electroniccounters are combined with the main decimal counter to achieve anynumber of batch formulations proportioned on the basis of arithmeticratios established by the control settings selected on the counters.

film ETTRETEFER 1 SINGLE UNITS TENS PULSE E 55L.

soURcE swrrcn HUNOS SEL.

H6. 2) SWITCH PULSE SHAPER 3 BINARY COUNTER MATERIAL DISPENSING UNITPATENTEDSEPMIQII 3,604,903

SHEEI 2 UF 2 COUNTER 32 DATA INPUT VOLTAGE SOURCE VOLTAGE SOURCE PULSET0 COUNTERS 24 GENERATOR 26 8 [FAWCTTfib'E c oUNTER 22 zfi zg' r r 40and SINGLE 229% g? UNITS TENS nuwoslfi THOU i I PULSE souncs L J LSTROBE u-un smoas STROBE IT? i T STROBE MECHANCAL DIODE 8 RESISTOR Lsmcnnomzmou NETWORK l L 5 ggwg INVENTQRS L w L 2 48 READER NEIL B. HOWESPOmER 4 aw jj P Q LQ MrJM/L ATTORNEYS MATERIAL DISPENSING CONTROL SYSTEMBACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates generally to control systems for weighing materials in differentdesired amounts or proportions, and pertains more particularly to meansfor generating a prescribed but adjustable number of output pulses whereeach pulse provides for metering or dispensing a fixed amount ofmaterial.

2. Description of the Prior Art In the preparation of batches ofmaterial, it is necessary to bring various ingredients together inprescribed amounts repeatedly. This is particularly true in themanufacture of concrete blocks, ready-mix concrete, animal feeds,fertilizer, etc. In systems which automate the batching process, variousanalog methods have been employed which compare the weight or volume ofeach material against a predetermined criterion. Usually this isaccomplished by producing an electrical or mechanical analog of theactual weight which is compared in an electrical or mechanicalcomparator with a similar analog representing the desired weight of thematerial. In certain of such systems the analog representation isaccomplished by changing the angular position of a separate pointermechanism which is attached to the face of a dial scale used to weighthe delivered material. The separate pointer cooperates with a weighingpointer to regulate the feeding mechanism for the material beingdispensed. The feeding mechanism is started by an initiating command,but is slowed and/or stopped by the coincidence of the two pointers onthe face of the dial scale. Systems of this type are simple and operatewell in many situations where the same batch composition and size isrepeatedly reproduced. However, where it is desired that each successivebatch be of a different composition, or of a different size, thenecessary modifications to the analog representation of the desiredmaterial weights is usually tedious and complex. Many prior art systemscannot be used outside a fixed range of batch sizes or weights, unlessextensively modified by addition and substitution of various electronicand mechanical components.

SUMMARY OF THE INVENTION Accordingly, the principal object of thepresent invention is to provide a material dispensing system that eitherobviates or minimizes the shortcomings of the material-dispensingsystems presently available, particularly with respect to their lack ofversatility. Another object of the invention resides in a dispensingsystem which employs digital representations of the various quantitiesbeing dispensed without resorting to elaborate mechanism usuallyassociated with digital approaches to this control function.

A further object of this invention is to provide the functions ofaddition, multiplication and division of the prescribed materialquantities without utilizing dataprocessing elements more complex thansimple pulse counters.

Briefly stated, our invention includes a pulse generator that produces atrain of pulses in response to an initial stimulus achieved by closing aswitch. The number of pulses is representative of the desired quantityof material being dispensed and is determined by control settingsselected on a main decimal counter. When the prescribed number of pulseshave been delivered, the main decimal counter produces a stop signalwhich terminates the generation of pulses and hence, the dispensing ofmaterial is terminated at the desired quantity. Through the interventionof secondary electronic counters, a large variety of arithmetic ratiosbetween the number of pulses and a given state of the decimal counter isachieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram exemplifyingthe preferred embodiment of the present invention.

FIG. 2 is a diagrammatic view showing the detailed construction of oneof the selection switches associated with the main decimal counter.

FIG. 3 is a diagrammatic view showing the detailed construction of theselection switch associated with one of the binary counters.

FIG. 4 is a diagrammatic view showing a modified form of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, theinvention is best understood by keeping in mind that the generalobjective of the entire system is to produce a train of electricalsignals or output pulses at 9 which are effective to control thematerial dispensing unit 11. Pulse count rather than .pulse frequency isthe measuring signal to a mechanical incrementer 12 which affords ananalog control of the dispensing unit 11. For simplicity, the detailedconstruction of the analog incrementer 12 is not shown, but in apreferred form, the mechanical incrementer 12 consists of an auxiliaryrotatable pointer on the face of a dial scale. This auxiliary pointercarries an illuminating lamp and cooperating photocell, and the normalweight indicating pointer carries an opaque member which passes into thelight path when the two pointers are coincident. The resultinginterruption of the light beam on the photocell stops operation of thedispensing unit 11. The positioning of the auxiliary pointer is by meansof a stepping motor and an associated gear train, so proportioned thatone or more electrical pulses to the stepping motor results in theadvance of the pointer by exactly one weight unit. Normally, the motoris driven by a controlled series of pulses only in the upscaledirection, and is later returned by the continuous application of pulsesterminated only when the pointer reaches its zero position on the dial.

Each cycle of operation is started by closing switch 14. This appliesvoltage from a single power source 15 to a controlled oscillator orpulse generator 17, causing the generator 17 to produce a train ofequally spaced pulses at 16. The frequency of these pulses depends uponthe requirements of the analog incrementer l2, i.e. the pulse rate mustbe rapid enough so the time required to complete the dispensing is notobjectionably long not so rapid as to exceed the acceleration rates ofthe mechanical devices. A preferred pulse rate is in the range of 25 to4,000 pulses per second. Closing switch 14 also applies voltage via path18 to a first single-pulse source 20 and second single-pulse source 22.Circuit constants are chosen for the pulse generator 17 and each of thesingle pulse sources 20 and 22 such that the single pulses from 20 and22 precede the initial pulse of generator 17. Also, the pulse fromsingle-plus source 20 precedes that produced by pulse source 22.

Our invention employs four electronic counting devices: a main decimalcounter 24, a first binary counter 26, a second binary counter 28, and athird binary counter 30. Each counter is an integrated electroniccircuit (IC) and includes one or more sets of bistable storage elementsor flip-flops, each of which transfers back and forth between its twostable states upon reception of short duration (0.5 microseconds)pulses. The pulses to be counted are applied to one of the bistableelements. Each time this binary element changes from the staterepresenting 1" to the state representing 0, a

pulse is caused to be sent to the next element in the set, and

this process continues in a similar manner for all of the bistableelements in each separate counter. when the decimal number system isused, such as in counter 24, elements having four binary flip-flops and10 stable states are used; and each time a given element changes fromthe state representing 9" to the state representing 0," a pulse is sentto the next element; It should also be noted in FIG. 1 that the inputterminal of each counting device is consistently shown on the left-handside of its rectangular block.

In operation, each of the counters moves through a prescribed successionof states as pulses are received at its input terminal. From an initialstate of all zeros," a counter accumulates pulses until it reaches itsfull capacity state,"

which corresponds to 9 on a decimal counter or 3," 7, or 31" in the caseof binary counters (depending upon the number of flip-flops). Transitionfrom the full capacity state to the zero state occurs whenever a counterreceives one additional pulse. This is referred to as the carry, and mayconstitute the input pulse to a succeeding counter. The carry isconsistentlyshown as leaving the right-hand of each block representingthe individual counter.

The main control counter 24 includes four decimal counter units 32, 34,36 and 38 which are cascaded to provide units, tens, hundred's andthousands decades, respectively. Corresponding selector switches forinstalling an initial setting on these decimal counters are designatedby the numerals 32a, 34a, 36a and 38a, respectively. Four wiresinterconnecting each of the counters with their respective selectorswitch are designated by the numerals 32b to 38b.

It is a property of the flip-flop counting elements employed in thisinvention that they possess a set of input terminals and gates such thata preset condition may be continuously applied to the input terminal foreach flip-flop which will, only when simultaneously accompanied by apulse input on a strobe" terminal, preset the flip-flop to a selectedone of its two states. By the employment of this property, a set of DCvoltages may be established by a corresponding set of single poleswitches representative of a preset number to which the associatedflipflops will be set upon the occurrence of the strobe. By this means,each of the counters may be caused to assume a preset number betweenzero and its full counting range each time the strobe occurs, and thusthe number of normal input pulses required for the production of thecarry may be arbitrarily established at any desired value. Countingdevices having this presettable property are commercially available fromseveral manufacturers, and those designated as N-8280 and N-8281"constitute decimal and binary devices available from the SigneticsCorporation, 811 East Arques Avenue, Sunnyvale, Calif.

Asexplained above, the number of pulses required at the input terminalof each of the decimal counters to cause a carry is equal to their fullcounting range minus the present state of the flip-flops. in otherwords, for each state of the flip-flops, a specific number of inputpulses is required to produce the carry. For example, when the state ofthe flip-flops in a decimal counter corresponds to the state 9, oneadditional input pulse will produce a carry; when 8, two input pulses;when 7," three, etc. Of course, if the flip-flops are in their initialzero state, then 10 input pulses are required to produce the carry.Extending this concept to the cascaded counter units of the main controlcounter 24, the carry from the highest order or thousands counter 38will occur after the number of input pulses is equal to l0,000 minus theinitial state placed on the flip-flops by the combined settings of theselector switches 32a, 34a, 36a and 380. it will be apparent that thedigital value of these combined settings on the selector switches 32athrough 38a may be any number between 0000" and In the case of the firstbinary counter 26, it is convenient to have the carry from its highestorder stage (normally 2 or 32) produce the strobe, and preset thecounter to some prescribed number after each carry and before thearrival of the next counting pulse from the generator 17. By this means,the same presettable property permits the application of DC voltagesover long wires to adjust the number of input pulses needed to producethe carry to any value between 1 and 32. in consequence of this feature,the number of pulses produced the generator 17 for a single input pulseto counter 32 or to a pulse shaper 44, respectively. Normally thesecounters provide selectable ratios of pulses between the generator 17and the connected device by utilization of all or fewer than all oftheir flip-flops; and the completely arbitrary selection systemdescribed for counter 26 is not employed. It is possible, however,should some not otherwise available ratio be required, that the strobingmechanism used in counter 26 could be employed in either.

It is the function of counter 30 to increase the number of input pulsesproduced by the generator 17 for each input pulse to the shaper 44. Aswill subsequently be described, this action provides for arithmeticdivision of the material amount. In a similar manner, the function ofcounter 28 increases the number of pulses from the generator 17 requiredfor each input pulse to the counter 32; however, by its placement in thesystem, this action results in multiplication of the number of pulses tothe shaper 44 for a given setting of the decimal selector switches32a-38a.

Main control counter 24 is shown having a feedback loop 40 fortransmitting a stop signal to pulse generator 17 when the counter 24issues its end carry. As described above, the number installed onselector switches 32a through 38a will determine the total number ofinput pulses to counter 24 needed to cause this end carry and produce astop signal to pulse generator 17. These settings therefore determinethe number of pulses required to stop generator 17 and hence shut downthe entire material dispensing system. Our circuitry is such that oncethe pulse generator 17 has been stopped, it cannot produce another trainof pulses until the stimulating switch 14 has opened and reclosed.

Two single pulse sources 20 and 22 are provided, both stimulated by theapplication of energy from the power supply 15 via the initial stimulusswitch 14. This switch, which normally closes to initiate the systemaction, and remains closed until after the desired material amount hasbeen dispensed stimulates the production of one single short-durationpulse from each of these two devices. The pulse from pulse source 20 isutilized to preestablish the state of. all counters in the system,except the binary counter 26, and normally results in counters 28 and 30taking their zero state. In the case of counter 24, it causes therepresentation produced by the switches 32a through 38a to be impressedon their respective decimal counters. Having accomplished this action,this pulse source remains quiescent until the switch 14 is opened andreclosed. Due to the very short time between closure of this switch andthe production of this pulse, it is imperative that there be no bouncein the switch contacts. The duration of this time is typically tomicroseconds.

As explained previously, the number value applied to the main controlcounter 24 by the settings on the selection switches 32a through 380should be 10,000 minus the number of input pulses desired. Expressedanother way, the switches specify a digit value equal to 9 minus thedesired value for each decimal digit except the most right-hand nonzerodigit which will be 10 minus the desired value. This expression of anumber is commonly called the tens complement. As explained by author R.K. Richards on page l6 of his book entitled Arithmetic Operations inDigital Computers," the term tens complement in not to be interpreted tomean that each individual digit is a tens complement. Actually, only thelowest order or least significant nonzero digit is a "ten's complement"of the true digits; higher order digits are nines complements. Forexample, the tens complement of 4,680 is 5,320.

From this, it is apparent that the tens complement expression is notuniformly related to the digit value for every column. Furthermore, thedigital relationship for the ten's complement expression would change aszeros appear in the rightmost columns. It is therefore desirable toproduce a completely uniform expression in complementary form.

To produce the completely uniform expression in complementary form, ourinvention first employs a nines complement" expression in the selectionswitches 32a to 38a, then applies a precount" of one pulse to counter 24to convert the nines complement to a tens complement. The ninescomplement with reference to the cascade counters 32 to 38 is valueequal to 9999 minus the desired number of output pulses before thecounter 24 issues the end carry; and it differs from the tens complementby exactly one unit. If it were to be used uncorrected,the number ofimpulses to produce an end carry of counter 24 would always be thedesired number plus one and would permit tolerable operation only inspecial cases. As will be readily appreciated, the percentage errorwould increase with smaller material amounts.

With our invention, it is possible to correct the nines complement, andthus permit its use in the switches 32a to 38a, and thereby permit everydigit to deliver to the counter 24 a value equal to nine minus thedesired value. The correction takes the form of applying an extra inputpulse to the counter 24 after the counter has assumed the ninescomplement state and before it has received the first of its normalinput pulses. This is the function of the second single-pulse source 22.The pulse source 22 thus provides a single pulse to the units counter 32of main control counter 24 and this pulse occurs about 50 microsecondsafter the strobe pulse, which is still considerably in advance of theproduction of the first pulse generated by pulse generator 17. Morespecifically on OR gate 21 having a pair of input terminals 21a, 21b andan output terminal 210 is employed. The input terminal 21a is connecteddirectly to the single pulse source 22 and the input terminal 21b to theoutput of the binary counter 28. As will become apparent hereinafter,the gate 21 assists in eliminating an inaccurate operation that wouldotherwise occur.

To illustrate the foregoing by example, presume that we desire thecounter 24 to carry after receiving 123 input pulses. The ninescomplement of 123 is 9876, which is produced in the counter 24 by thecombined action of the switches 32a to 38a and the strobe as has beendescribed. Were this to remain uncorrected, the end carry would beproduced after 124 input pulses. However, by applying the one pulseprecount the counter advances from 9876 (nines complement) to 9877 (tenscomplement). Accordingly, only the desired quantity of 123 additionalpulses are required to cause the end carry and shut down pulse generator17.

Reference is now made to FIG. 2 where the special properties required ofswitches 32a, 34a, 36a and 38a are illustrated. Since switches 32a to380 are similarly constructed, only switch 32a is shown in detail. Eachof these switches is most conveniently implemented by a single-polel0-position switch at 50, marked 0 through 9. This implementation ischosen since it also is compatible with conventional punched cardreading devices. It is necessary, however, that the output from eachswitch be in a nines complement form and binary coded on four wires,designated generally by the numeral 32b. This conversion is readilyaccomplished in the manner shown by the interconnection of diodes 52,between the nine switch positions marked 0" through 8, and four voltagedividers 54. In the absence of an applied voltage, each divider 54provides a circuit path to ground 56 on one of the four binary-codinglines 3212 which are taken to the data input terminals of units counter32. The value of the voltage from source and the ratio of the voltagedividers 54 are completely arbitrary requiring only that a suitablevoltage (2.5 to 3.0 volts) is available for application to theintegrated circuit counting modules data input when the voltage isconnected. Since the nines complement of 9 is zero, no connection isnecessary for the value of nine.

Although the foregoing explanation presumed the continuous applicationof DC voltages to the data inputs of the decimal counter 32 through 38via switches 32a through 380, it is only necessary that these voltagesbe present during the fractional microsecond interval coincident withthe strobe pulse from single pulse source 20. Advantage may be taken ofthis circumstance to provide a very useful variation of the previouslydescribed invention by supplying the data inputs to the individualdigits of the counter 24 from a single decimal source and selecting theparticular stage of the counter to which the decimal value is applied byselection of the strobe application. This embodiment is particularlyuseful when the values of the material amount arise from the reading ofpunched cards.

FIG. 4 illustrates the replacement of first pulse source 20, switch 14and decimal switches 32a through 380 with a set of card reading switches48, a diode resistor network 46 (identical in electrical connection andfunction to that shown in FIG. 2 and identified as 52 and 54), afive-position mechanically operated switch 70, four capacitors 72, 74,76, 78 and a resistor 68 for each capacitor. The date inputs to allstages of counter 24 are now shown connected in parallel so that anydata expression on these four wires will be simultaneously applied toall stages of counter 24.

This variation of the invention commences each cycle of operation byreading a card column relevant to the data required by counter 38, andsimultaneously connecting a multiple position switch 70 or pulsedistributor to capacitor 78 to apply suitable strobing to only thethousands counting element. As the next card column passes through thecard reader, the data relevant to the hundreds digit is applied to thehundreds counter via diode and resistor network 46 while simultaneouslyswitch 70 connects to capacitor 76 to strobe the hundreds counter 36.The tens and units digits operate successively in the same manner, andthen switch 70 moves to its fifth position to apply power to pulsegenerator 17 and single pulse source 22. At this point the remainder ofthe cycle of operation is identical as in the original invention. It issignificant that this embodiment of the invention permits the data froma series of successively read card columns to determine the amount ofmaterial dispensed without the employment of any intervening datastorage mechanism.

To clarify the function of the electronic binary counters 26, 28 and 30,we might consider the operation of the system assuming these counters tobe absent. This assumes that the output of the pulse generator 17 isconnected directly to the input of the counter 24 and to a pulse shaper44, shown in parallel electrical relationship. The function of the pulseshaper 44 is to increase the power level and duration of the generatorpulses to levels compatible with the mechanical or electromechanicalmechanism used to produce the incrementing of the analog incrementer 12.For simplicity, circuit detail is not shown, but usually a conventionalmonostable multivibrator is used for this purpose.

With none of the three binary counters 26, 28 and 30 present, the numberof pulses emitted at 9 by the pulse shaper 44 after closure of theswitch 14 will be exactly the same number required to produce shutdownof pulse generator 17 via the stop signal from counter 24. Thus, thenumber of pul ses will be equal to the tens complement of the numberinstalled via the selection switches 32a to 38a. For convenience, as hasbeen shown in FIG. 2, the dials of these switches are labeled so as todisplay the desired number instead of its complement.

Now presume the same configuration except with the addition of thebinary counter 26. Note that counter 26 is initially preset by theprecount pulse from single pulse source 22 and then operates its ownstrobe on each subsequent end carry. In this regard, an OR gate 23 isutilized having a pair of input terminals 23a, 23b and an outputterminal 23c. The input terminal 23a is connected directly to the pulsesource 22, whereas the input terminal 23b is connected to the outputfrom the binary counter 26. The output terminal 23c is connected to thestrobe terminal of the counter 26 which has been labeled 260. Thus,through the agency of the OR gates 21 and 23, any output pulse from thebinary counter is prevented from being applied to the strobe terminal26c of the binary counter 26, and any output pulse from the counter 26is prevented from being forwarded as an input pulse to the main controlcounter 24. Note also that when counter 28 is not present, this carrybecomes the input to the unit's counter 32 of main control counter 24.The pulse shaper 44 remains'connected directly to the output of thepulse generator 17. If

under this condition, the selection switch 26a is set to the two'scomplement" of one, an output from the carry of the counter 26 willoccur for each pulse it receives from the generator 17, since each carrywill preset the counter to 31 from whence the next oscillator pulse willcause another carry. Thus, the addition of the counter 26 will notchange the operation of the system from that of not using counter 26when switch 26a is set in the manner described. However, for valuesinstalled on selection switch 26a which are less than 3 l the pulsegenerator 17 must produce a greater number of pulses for each carry andadvance of the units counter 32. In this manner, we accomplishmultiplication in the production of output pulses from the pulse shaper44, since the pulse shaper continues to make one output pulse for eachpulse from generator 17.

The special properties of switch 26a are illustrated in detail in FIG.3. For an embodiment permitting 32 selections for the value of themultiplier contributed by counter 26, a five-pole 32-position switch 60or its equivalent is required. This switch is marked and wired as shownin FIG. 3 so that in the position marked l," voltage applied to all fivevoltage dividers 62 for application to the data input to the counter 26via the five wires 26b. This implementation actually represents thenumber 31 (the two's complement of one in a modulus 32 system) andfunctions to preset counter 26 to the binary number 3 l upon theapplication of the precount pulse and upon each carry from counter 26thereafter. Thus, setting the switch 26a to the position marked "1 willresult in the counter 26 producing a carry after each input pulse. Whenswitch 26a is set to the position marked 2," the precount pulse andsucceeding carry pulses preset counter 28 to the binary number 30 andcarries are produced regularly after each two input pulses. In thismanner, switch 26a may select any number between 1" and 32 inclusive,for the effective multiplier of the weight amount represented by thesetting of switches 32a through 38a. Although not shown in completedetail, it will be obvious that the 2 output line of the switch willhave the first positions wired in parallel, and no connection to thelast 16.

Relating this multiplication feature to the batching process, it is nowpossible, by the selection of a value for counter 26 (as preset onswitch 26a) to multiply the value installed on counter 24 for a standardsize batch by an integer and thereby have one cycle of operation producean analog representing a multiple of the standard size batch. By markingthe selection switch 260 appropriately, its positioning can easily beperformed to achieve specific multiples despite the fact that theswiteh's contacts express a two's complement. Thus, it is convenient toconsider the binary counter 26 as a multiplier of decimal counter 24.

If we assign the letter A to represent the number values installed inswitches 32a-38a, and the letter 8" to represent the value set on switch26a, the number of output pulses produced at 9 can be expressedmathematically as follows:

No. of output pulses AXS Consider now the addition of the third binarycounter 30. This counter is also an IC counting element and by adding itto the system another factor may be achieved in determining the numberof pulses delivered at 9 to the analog incrementer 12. In the design ofthe counter 30, for the preferred embodiment of the invention, we havedetermined that only a limited number of values have practical value,and it is convenient to select from the various intermediate terminalsof the flip-flops so as to have one input to the pulse shaper 44 for aprescribed number of pulses produced by generator 17. For purposes ofthe preferred embodiment, these values typically include 2,38 4, 5,""8," 10" and I6, the value l being superfluous since it is achieved alsoby the omission of the counter 30. Any one of these values can beselected and wired into the input of the pulse shaper 44 with the resultthat the pulse generator 17 is required to make that many pulses foreach output pulse produced at 9 to the analog incrementer 12. Thisplaces the value of counter 30 into the denominator of the expressionfor the number of output pulses produced at 9, and has the practicalpurpose of permitting the dispensing of fractional amounts of thedesired A" value without changing the value actually expressed by theselection switches 32a-38a If the letter M" is used to designate thenumber of value of binary counter 30, and a concurrent selection is madeon counter 26, the mathematical expression for delivery of output pulsesat 9 becomes as follows:

No. of output pulses AXS/M where A" represents the number of weightunits in a standard size batch, and SIM represents the relationship ofthe actual batch size to a standard batch size. We will now apply thismathematical relationship to a specific example in the batching process.If S" is chosen as 5 and M" is chosen as 4, then the number of pulsesdelivered from pulse shaper 44 would be 5/4 of "A." Accordingly, a batch1% times a standard batch would be produced.

The function of counter 28 is somewhat similar to that of counter 26,since it causes the number of generator pulses to be multiplied by theparticular value selected for the counter 28. Its principal value is toprovide accommodation for the actual gear train used between a steppingmotor and the mechanical analog incrementer 12 so that the requirementof one pulse for one unit of the dimension used for A" can becircumvented. For example, by making counter 28 equal to 2," the numberof output pulses for a given situation can be doubled to accommodate acondition where one output pulse moves the analog incrementer 12 onlyonehalf of a weight unit. If the letter G is used to designate the valueof counter 28, then the final mathematical expression for the outputpulses is as follows:

No. of pulses AXSXG/M The values of S, M and 0 may be combined toaccommodate nonintegral values required for gear and motor combinationsmore complex those simple conditions described.

ln a practical application of our material-dispensing system, such asfor the automatic batching of concrete, the value A" set on counter 24has a different value for each successive material or ingredient that isdispensed into a single batch. Thus, separate settings of switches32a-36a may be successively made, or alternatively a separate switchgroup may be provided for the desired quantities of sand, cement, andaggregate, or additives. When such separate switches are provided,successive operations of the switch 14, during the accumulative weighingof several material into a single weighing mechanism, results in theaddition of individual representations weight of successive materialswithout the necessity of a digital adder. This is accomplished by thesuccessive operation of the control system to advance the analogcriterion on the scale dial without returning the latter to its staringposition. Simultaneously a different set of switches 324 through 38a isenergized by reconnection of the power input wire 15. Each set of suchswitches represents the amount of the relevant material to be added tothe batch. By so doing, the criterion after each operation of thecontrol system represents the sum of the most recent advance plus allprevious advances since it was last reset, while the control systembehaves only in response to the current material value. The systemthereby permits the individual adjustment of the amount for any materialwithout having to make any compensating adjustment of other materialamounts to be weighed subsequent to the one altered.

The 8" value on counter 26 may take a different value for successivebatches, as the demand for different size batches of differentformulations prescribes. As described above, this is achieved by merelymaking the desired selection on the switch 26a. The values G and M forcounters 28 and 30, respectively are usually fixed at the time of thedesign of the system and are considered constants in a given embodiment.Nevertheless, the ease in which they can be changed permits greatflexibility of application of our material-dispensing system. Theinvention's versatility may be further enhanced through the use of apunched card reader which supplies the desired A values to the counter24 via a punched card containing the recipe" for a standard-sized batch.

It will be apparent to those skilled in the art that ourmaterial-dispensing system may be modified to achieve yet anotherdesired embodiment. in this embodiment, a material-feeding device iscaused to produce one pulse for each unit of weight, (or fractional unitof weight), as it delivers material to a receiving vessel. If thesepulses are used in the described system in lieu of those generated bythe pulse generator 17, and ifthe material-feeding device is stopped bythe issuance of the end carry from counter 24, a very practicalmaterialdispensing system employing the digital control systempreviously described may be implemented.

A still further embodiment utilizing the invention is possible byproviding a material-dispensing device which delivers one unit ofmaterial for each pulse received. In such embodiment, the pulsesproduced by shaper 44 appearing on output line 9 are applied directly tosuch material-dispensing device. An appropriate adjustment of the pulsegenerator frequency may be made to accommodate a very wide variety ofsuch dispensing devices without requiring any other alteration of thedescribed system.

We claim:

1. A system for controlling the dispensing of a materialcomprising meansfor dispensing a predetermined amount of material in accordance with anumber of pulses supplied thereto, pulse-generating means for producinga train of pulses, means connecting said material-dispensing means tosaid generating means so at least a proportional number of pulsesproduced by said generating means are received by said dispensing means,a main control counter means having an input terminal and an outputterminal, selection means for installing an initial setting into saidmain control counter means, said setting having a value indicative of aquantity of material to be delivered by said dispensing means, anauxiliary counter means having an input terminal connected to saidpulsegenerating means and an output terminal connected to the inputterminal of said main control counter means for forwarding a pulse tosaid main control counter means only after a certain number of pulsesfrom said pulse-generating means have been counted, selection meansconnected to said auxiliary counter means for presetting said auxiliarycounter means to cause said auxiliary counter means to forward a pulseto said main control counter means after a certain number of pulses fromsaid pulse-generating means have been counted by said auxiliary countermeans, the setting installed by said selection means determining saidcertain number of pulses and thereby causing the value represented bysaid first-mentioned selection means to be multiplied by an integerdetermined by the setting of said last-mentioned selection means, meansconnected to the output terminal of said auxiliary counter means forresetting said auxiliary counter means to the setting installed by saidlast-mentioned selection means each time a pulse is forwarded to saidmain control counter means, means connected between the output terminalof said main control counter means and said pulse-generating means forterminating said pulse train after said main control counter has counteda number of pulses determined by the setting of said first-mentionedselection means, and means for providing a single pulse to the inputterminal of said main control counter means prior to receipt of a pulsefrom the output terminal of said auxiliary counter means, whereby thenumber of pulses supplied to said material dispensing means, and theamount of material delivered therefrom, is determined by both said maincontrol counter and said auxiliary counter.

2. The control system of claim 1 in which the resetting means for saidauxiliary counter means includes a strobe terminal and means connectedbetween the output terminal of said auxiliary counter means and saidstrobe terminal for applying each output pulse at the output terminal ofsaid auxiliary counter means to said strobe terminal to effect theresetting of said auxiliary counter means to said installed setting.

3. The control system of claim 2 including means connecting said singlepulse means to said strobe terminal and to said input terminal of saidmain control counter means so as to assure application of a single pulseto said input terminal of said main control counter means prior toreceipt of any pulses from the output terminal of said auxiliary countermeans.

4. The control system of claim 3 in which said auxiliary counter meansincludes a plurality of stages and said selection means thereforincludes a switch connected to each of said stages for installing adesired setting into each stage whereby said certain number of pulsescan be changed to different number and thereby cause the value installedon said main control counter means to be multiplied by an integerdetermined by the setting of said last-mentioned selection means.

5. The control system of claim 3 including a second auxiliary countermeans, said second auxiliary counter means being connected between saidpulse-generating means and said material-dispensing means for countingpulses from said generating means and providing a pulse to saidmaterialdispensing means only after a predetermined number of pulseshave been counted, thereby proportionally reducing the number of pulsesfrom said generating means that would otherwise be supplied to saidmaterial-dispensing means.

6 A system for controlling the dispensing of a material-comprising meansfor dispensing a predetermined amount of material in accordance with anumber of pulses supplied thereto, pulse-generating means for producinga train of pulses, means connecting said material-dispensing means tosaid generating means so at least a proportional number of pulsesproduced by said generator means are received by said dispensing means,a main control counter including a plurality of counting units arrangedto denote various ascending numerical orders, means for presetting eachof said counting units in accordance with the complement of datacontained on a card to deten'nine the number of pulses supplied to saiddispensing means, said presetting means including a multiple positionswitch and a column of card operable switches which multiple positionswitch successively strobes said counting units to cause each countingunit to be preset to a value in accordance with data contained in columnform on said card, said multiple-position switch including a positionfor causing said pulse-generating means to supply said train of pulses,and a single-pulse means connected to the lowest order unit of said maincontrol counter, said multiple-position switch causing a pulse to besupplied to said lowest order counting unit prior to receipt of anypulses derived from said pulse-generating means.

7. The control system of claim 6 including means connected between thehighest order unit of said main control counter and saidpulse-generating means for terminating said pulse train after said maincontrol counter has counted a number of pulses determined by saidcard-operable switches.

8. A system for controlling the dispensing of a materialcomprising meansfor dispensing a predetermined amount of material in accordance with anumber of pulses supplied thereto, pulse-generating means for producinga train of pulses, means connecting said material-dispensing means tosaid generating means so at least a proportional number of pulsesproduced by said generating means are received by said dispensing means,a main control counter including a plurality of counting units arrangedto denote various ascending numerical orders, selection means includinga switch for each counting unit for installing an initial setting intothe counting unit with which it is associated, said switch settingscollectively having a value indicative of a quantity of material to bedelivered by said dispensing means, an auxiliary counter connectedbetween said pulse-generating means and the lowest order unit of saidmain control counter for forwarding a pulse to said main control counteronly after a certain number of pulses from said pulse generator havebeen counted, means connected between the highest order unit of saidmain control counter and said pulse-generating means for terminatingsaid pulse train after said main control counter has counted a number ofpulses determined by said switch settings, means for providing a singlepulse to the lowest order counting unit, said auxiliary counter having astrobe terminal, means connecting said single-pulse means to said strobeterminal and to said lower order counting unit so as to assureapplication of a single pulse to said lower order counting unit prior toreceipt of airy pulses from said auxiliary counter, said connectingmeans including an OR gate having a pair of input terminals and anoutput terminal, one of said input terminals being connected to saidsingle-pulse means, the other of said input terminals being connected tosaid auxiliary counter and said output terminal being connected to saidstrobe terminal, whereby a pulse from said single-pulse means or a pulsefrom said auxiliary counter establishes a particular state of saidauxiliary counter, the number of pulses supplied to said materialdispensing means, and the amount of material delivered therefrom,thereby being determined by both said main control counter and saidauxiliary counter.

9. The control system of claim 7 including a second OR gate having apair of input terminals and an output terminal, one of saidlast-mentioned input terminals being connected to said single-pulsemeans, the other of said last-mentioned input terminals being connectedto said auxiliary counter and said lastmentioned output terminal beingconnected to said lowest order unit of the main control counter, wherebysaid lowest order unit receives pulses from either said single-pulsemeans or from said auxiliary counter.

10. A system for controlling the dispensing of a materialcomprisingmeans for dispensing a predetermined amount of material in accordancewith a number of pulses supplied thereto, pulse-generating means forproducing a train of pulses, means connecting said material-dispensingmeans to said generating means so at least a proportional number ofpulses produced by said generating means are received by said dispensingmeans, a main control counter including a plurality of counting unitsarranged to denote various ascending numerical orders, selection meansincluding a switch for each counting unit for installing an initialsetting into the counting unit with which it is associated, said switchsettings collectively having a value indicative of a quantity ofmaterial to be delivered by said dispensing means, an auxiliary counterconnected between said pulse generating means and the lowest order unitof said main control counter for forwarding a pulse to said main controlcounter only after a certain number of pulses from said pulse generatorhave been counted, means connected between the highest order unit ofsaid main control counter and said pulse generating means forterminating sad pulse train after said main control counter has counteda number of pulses determined by said switch settings, means forproviding a single pulse to the lowest order counting unit prior toreceipt of a pulse from said auxiliary counter, said auxiliary counterhaving a strobe terminal, means connecting said single-pulse means tosaid strobe terminal and to said lower order counter unit so as toassure application of a single pulse to said lower order counter unitprior to receipt of any pulses from said auxiliary counter, a secondauxiliary counter, said second auxiliary counter being connected betweensaid pulse-generating means and said material-dispensing means forcounting the pulses from said generating means and providing a pulse tosaid material-dispensing means only after a predetermined number ofpulses have been counted, thereby proportionally reducing the number ofpulses from said generating means that would otherwise be supplied tosaid material-dispensing means, and an additional single-pulse means forpresetting the counting units of said main control counter and saidadditional auxiliary counter, said additional single-pulse meanssupplying its pulse in advance of the pulse supplied by saidfirst-mentioned single-pulse means.

11. The control system of claim 10 including a switch for applyingvoltage from a single power source to said pulse generating means and toboth of said single-pulse means, the circuit constants of saidgenerating means causing the production of the single pulse from both ofsaid single pulse means to precede the initial pulse for said generatingmeans.

12. A system for controlling the dispensing of a materialcomprisingmeans for dispensing a predetermined amount of material in accordancewith a number of pulses applied thereto, pulse-generating means forproducing a train of pulses, means connecting said material-dispensingmeans to said generating means so at least a proportional number ofpulses produced by said generating means are received by said dispensingmeans, a main control counter including a plurality of counting unitsarranged to denote various ascending numerical orders, means forpresetting each of said counting units in accordance with data containedon a card to determine the number of pulses supplied to said dispensingmeans, each of the counting units of said main control counter beingprovided with a strobe terminal and the system further including adistributor for sequentially supplying strobe pulses to each of saidcounting units, said distributor thereafter supplying a command to saidpulse-generating means to produce said train of pulses.

13. A system for controlling the dispensing of a material comprisingpulse-generating means for producing a train of pulses, a main controlcounter including a plurality of counting elements arranged to denotevarious ascending numerical orders, feedback means connected from theoutput of the highest order counting element to said pulse-generatingmeans for terminating the pulse train after a predetermined number ofpulses representative of a desired amount of material have been countedby said main control counter, means for presetting the counting elementsof said main control counter so that said elements represent one lessthan the arithmetic complement of said desired amount, means forapplying a precount pulse to said main control counter prior to applyingpulses from said pulse-generating means so that said one less than thearithmetic complement is changed to the true arithmetic complement ofsaid desired amount, material dispensing means for delivering materialin accordance with the number of pulses supplied thereto from saidpulse-generating means, whereby the quantity of material delivered bysaid material-dispensing means is in accordance with the number ofpulses supplied to said main control counter after the application ofsaid precount pulse.

14. The control system of claim 13 in which said first-mentionedcomplement state is a nine's complement and said second-mentionedcomplement state is a tens complement.

5% UNlTED STATES PATENT ()FFICE CERTIFICATE OF CCRRECTEON Pa n 3.604.903Dated September 14. 1971 Inventor(s) John L. Hill and Neil B. Howes Itis certified that error appears in theabove-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Eolumn 2, line 50, "plus" should be --pulse--. Column 3, line 7 57,delete "-b". Column 5, line 23, "on" should be --an--.

Column 6, line 11, "date" should be --data. Column 7, line 69, delete"38" and insert Column 8, line 5, after "number" delete "of"; line 46,"material" should be --materials--; 18, after "tions" insert "of the--;line 51, "staring" ould be starting-a Column 10, line 11, after "to"insert e. Column 11, line 19, "7" should be --8--; line 47, "sad" shouldbe -said--. Column 12, line 15, "for" should be --from--; Eine 18,"applied" should be --Supplied--.

Signed and sealed this 21st day of March 1972.

(SEAL) Attest:

EDWARD M.FLETGHER, JR. ROBERT so TTSCHALK ain't-testing OfficerCommissioner of Patents

1. A system for controlling the dispensing of a materialcomprising means for dispensing a predetermined amount of material in accordance with a number of pulses supplied thereto, pulse-generating means for producing a train of pulses, means connecting said material-dispensing means to said generating means so at least a proportional number of pulses produced by said generating means are received by said dispensing means, a main control counter means having an input terminal and an output terminal, selection means for installing an initial setting into said main control counter means, said setting having a value indicative of a quantity of material to be delivered by said dispensing means, an auxiliary counter means having an input terminal connected to said pulse-generating means and an output terminal connected to the input terminal of said main control counter means for forwarding a pulse to said main control counter means only after a certain number of pulses from said pulsegenerating means have been counted, selection means connected to said auxiliary counter means for presetting said auxiliary counter means to cause said auxiliary counter means to forward a pulse to said main control counter means after a certain number of pulses from said pulse-generating means have been counted by said auxiliary counter means, the setting installed by said selection means determining said certain number of pulses and thereby causing the value represented by said first-mentioned selection means to be multiplied by an integer determined by the setting of said last-mentioned selection means, means connected to the output terminal of said auxiliary counter means for resetting said auxiliary counter means to the setting installed by said last-mentioned selection means each time a pulse is forwarded to said main control counter means, means connected between the output terminal of said main control counter means and said pulse-generating means for terminating said pulse train after said main control counter has counted a number of pulses determined by the setting of said first-mentioned selection means, and means for providing a single pulse to the input terminal of said main control counter means prior to receipt of a pulSe from the output terminal of said auxiliary counter means, whereby the number of pulses supplied to said material dispensing means, and the amount of material delivered therefrom, is determined by both said main control counter and said auxiliary counter.
 2. The control system of claim 1 in which the resetting means for said auxiliary counter means includes a strobe terminal and means connected between the output terminal of said auxiliary counter means and said strobe terminal for applying each output pulse at the output terminal of said auxiliary counter means to said strobe terminal to effect the resetting of said auxiliary counter means to said installed setting.
 3. The control system of claim 2 including means connecting said single pulse means to said strobe terminal and to said input terminal of said main control counter means so as to assure application of a single pulse to said input terminal of said main control counter means prior to receipt of any pulses from the output terminal of said auxiliary counter means.
 4. The control system of claim 3 in which said auxiliary counter means includes a plurality of stages and said selection means therefor includes a switch connected to each of said stages for installing a desired setting into each stage whereby said certain number of pulses can be changed to different number and thereby cause the value installed on said main control counter means to be multiplied by an integer determined by the setting of said last-mentioned selection means.
 5. The control system of claim 3 including a second auxiliary counter means, said second auxiliary counter means being connected between said pulse-generating means and said material-dispensing means for counting pulses from said generating means and providing a pulse to said material-dispensing means only after a predetermined number of pulses have been counted, thereby proportionally reducing the number of pulses from said generating means that would otherwise be supplied to said material-dispensing means. 6 A system for controlling the dispensing of a material-comprising means for dispensing a predetermined amount of material in accordance with a number of pulses supplied thereto, pulse-generating means for producing a train of pulses, means connecting said material-dispensing means to said generating means so at least a proportional number of pulses produced by said generator means are received by said dispensing means, a main control counter including a plurality of counting units arranged to denote various ascending numerical orders, means for presetting each of said counting units in accordance with the complement of data contained on a card to determine the number of pulses supplied to said dispensing means, said presetting means including a multiple position switch and a column of card operable switches which multiple position switch successively strobes said counting units to cause each counting unit to be preset to a value in accordance with data contained in column form on said card, said multiple-position switch including a position for causing said pulse-generating means to supply said train of pulses, and a single-pulse means connected to the lowest order unit of said main control counter, said multiple-position switch causing a pulse to be supplied to said lowest order counting unit prior to receipt of any pulses derived from said pulse-generating means.
 7. The control system of claim 6 including means connected between the highest order unit of said main control counter and said pulse-generating means for terminating said pulse train after said main control counter has counted a number of pulses determined by said card-operable switches.
 8. A system for controlling the dispensing of a material-comprising means for dispensing a predetermined amount of material in accordance with a number of pulses supplied thereto, pulse-generating means for producing a train of pulses, means connecting said material-dispensing means to Said generating means so at least a proportional number of pulses produced by said generating means are received by said dispensing means, a main control counter including a plurality of counting units arranged to denote various ascending numerical orders, selection means including a switch for each counting unit for installing an initial setting into the counting unit with which it is associated, said switch settings collectively having a value indicative of a quantity of material to be delivered by said dispensing means, an auxiliary counter connected between said pulse-generating means and the lowest order unit of said main control counter for forwarding a pulse to said main control counter only after a certain number of pulses from said pulse generator have been counted, means connected between the highest order unit of said main control counter and said pulse-generating means for terminating said pulse train after said main control counter has counted a number of pulses determined by said switch settings, means for providing a single pulse to the lowest order counting unit, said auxiliary counter having a strobe terminal, means connecting said single-pulse means to said strobe terminal and to said lower order counting unit so as to assure application of a single pulse to said lower order counting unit prior to receipt of any pulses from said auxiliary counter, said connecting means including an OR gate having a pair of input terminals and an output terminal, one of said input terminals being connected to said single-pulse means, the other of said input terminals being connected to said auxiliary counter and said output terminal being connected to said strobe terminal, whereby a pulse from said single-pulse means or a pulse from said auxiliary counter establishes a particular state of said auxiliary counter, the number of pulses supplied to said material dispensing means, and the amount of material delivered therefrom, thereby being determined by both said main control counter and said auxiliary counter.
 9. The control system of claim 7 including a second OR gate having a pair of input terminals and an output terminal, one of said last-mentioned input terminals being connected to said single-pulse means, the other of said last-mentioned input terminals being connected to said auxiliary counter and said last-mentioned output terminal being connected to said lowest order unit of the main control counter, whereby said lowest order unit receives pulses from either said single-pulse means or from said auxiliary counter.
 10. A system for controlling the dispensing of a material-comprising means for dispensing a predetermined amount of material in accordance with a number of pulses supplied thereto, pulse-generating means for producing a train of pulses, means connecting said material-dispensing means to said generating means so at least a proportional number of pulses produced by said generating means are received by said dispensing means, a main control counter including a plurality of counting units arranged to denote various ascending numerical orders, selection means including a switch for each counting unit for installing an initial setting into the counting unit with which it is associated, said switch settings collectively having a value indicative of a quantity of material to be delivered by said dispensing means, an auxiliary counter connected between said pulse generating means and the lowest order unit of said main control counter for forwarding a pulse to said main control counter only after a certain number of pulses from said pulse generator have been counted, means connected between the highest order unit of said main control counter and said pulse generating means for terminating sad pulse train after said main control counter has counted a number of pulses determined by said switch settings, means for providing a single pulse to the lowest order counting unit prior to receipt of a pulse from said auxiliary counter, said auxiliary counter havinG a strobe terminal, means connecting said single-pulse means to said strobe terminal and to said lower order counter unit so as to assure application of a single pulse to said lower order counter unit prior to receipt of any pulses from said auxiliary counter, a second auxiliary counter, said second auxiliary counter being connected between said pulse-generating means and said material-dispensing means for counting the pulses from said generating means and providing a pulse to said material-dispensing means only after a predetermined number of pulses have been counted, thereby proportionally reducing the number of pulses from said generating means that would otherwise be supplied to said material-dispensing means, and an additional single-pulse means for presetting the counting units of said main control counter and said additional auxiliary counter, said additional single-pulse means supplying its pulse in advance of the pulse supplied by said first-mentioned single-pulse means.
 11. The control system of claim 10 including a switch for applying voltage from a single power source to said pulse generating means and to both of said single-pulse means, the circuit constants of said generating means causing the production of the single pulse from both of said single pulse means to precede the initial pulse for said generating means.
 12. A system for controlling the dispensing of a material-comprising means for dispensing a predetermined amount of material in accordance with a number of pulses applied thereto, pulse-generating means for producing a train of pulses, means connecting said material-dispensing means to said generating means so at least a proportional number of pulses produced by said generating means are received by said dispensing means, a main control counter including a plurality of counting units arranged to denote various ascending numerical orders, means for presetting each of said counting units in accordance with data contained on a card to determine the number of pulses supplied to said dispensing means, each of the counting units of said main control counter being provided with a strobe terminal and the system further including a distributor for sequentially supplying strobe pulses to each of said counting units, said distributor thereafter supplying a command to said pulse-generating means to produce said train of pulses.
 13. A system for controlling the dispensing of a material comprising pulse-generating means for producing a train of pulses, a main control counter including a plurality of counting elements arranged to denote various ascending numerical orders, feedback means connected from the output of the highest order counting element to said pulse-generating means for terminating the pulse train after a predetermined number of pulses representative of a desired amount of material have been counted by said main control counter, means for presetting the counting elements of said main control counter so that said elements represent one less than the arithmetic complement of said desired amount, means for applying a precount pulse to said main control counter prior to applying pulses from said pulse-generating means so that said one less than the arithmetic complement is changed to the true arithmetic complement of said desired amount, material dispensing means for delivering material in accordance with the number of pulses supplied thereto from said pulse-generating means, whereby the quantity of material delivered by said material-dispensing means is in accordance with the number of pulses supplied to said main control counter after the application of said precount pulse.
 14. The control system of claim 13 in which said first-mentioned complement state is a nine''s complement and said second-mentioned complement state is a ten''s complement. 